---

数组

数组可以 append，不能 +

python">vids = ['a', 'b']

def t1():
    print('-- vids : ', vids) 

    vids.append('c')
    print('-- vids : ', vids) 

    vids += 'd' # 报错
    print('-- vids : ', vids) 
 

t1() 

---

没问题

python">def t3():
    
    global vids
    vids += 'd' # 报错
    print('-- vids : ', vids) 

---

字符

python">a = '1'
def t2():
    global a
    a = '2' 
    print('-- a : ', a) 

---

python">a = '1'
def t2():

    print('-- a : ', a) 
    # 报错 : SyntaxError: name 'a' is used prior to global declaration
    
    global a
    a = '2' 
    
    print('-- a : ', a) 

---

python">a = '1'
def t2():
    global a = '2' # 报错

---

使用模块化实现全局变量：

​​import​​​ ​​global_var_model as gl​​ 

https://blog.51cto.com/xiaohaiwa/5683078